Thiourethanes of cellulose ethers



limited States Fatent C THIOURETHANES OF CELLULOSE ETHERS Arthur L.Allewelt, West Chester, Pa., assignor to American Viscose Corporation,Philadelphia, Pa., :1 corporation of Delaware No Drawing. ApplicationApril 1, 1952, Serial No. 279,921

8 Claims. (21. 260--216) This invention relates to thiourethanes ofsubstitutedethyl celluloses and to compositions and molded and extrudedarticles comprising them. This case is related to Serial No. 353,901,filed May 18, 1953, same inventor.

The new ethers of the invention result from the interaction of theselected cellulose thiourethane with an acrylic acid derivative of theformula CH2 CHX in which X is the cyano group or the group CONYY inwhich Y and Y represent hydrogen or alkyl radicals containing from 1 to3 carbon atoms, whereby the cyanoethyl, amidoethyl, or alkyl-substitutedamidoethyl ether is formed by the 1,4 addition of the acrylic acidderivative to the cellulose portion of the cellulose thiourethane.

The products of the reaction between the cellulose thiourethane andacrylic acid derivative may be represented by the formula 8 R Oel1-O(}-N CH2CH2X \R in which cell represents the cellulose molecule, Xrepresents one of the groups set forth above, and R and R each representhydrogen, a saturated or unsaturated hydrocarbon radical containing from1 to 12 carbon atoms, an alicyclic or hydrocarbon-substituted alicyclicradical comprising a single 4- to 6-membered carbocyclic ring and havinga total of not more than twelve carbon atoms, a heterocyclic orhydrocarbon-substituted heterocyclic radical comprising a single 5- or6-membered ring and having a total of not more than twelve carbon atoms,an aryl radical of the benzene series, or in aryl radical of the benzeneseries having hydrocarbon groups containing a total of not more than sixcarbon atoms attached to the benzene ring, R and R being the same ordifferent.

Representative compounds within the scope of the invention include thecyanoethyl-, Z-amidoethyl, N-alkyl-2- amidoethyl, andN,N-dialkyl-2-amidoethyl ethers of cellulose thiourethanes in which thethiourethane group is one of the following:

Thiourethane Phenylthiourethane Phenylethylthiourethanelsopropylthiourethane Amylthiourethane BenzylthiourethaneCyclohexylthiourethane Octylthiourethane DibenzylthiourethaneDibutylthiourethane Die thylthiourethane PyridylthiourethaneEthylthiourethane Allylthiourethane MethallylthiourethanePyrrolylthiourethane Cyclobutylthiourethane F lC The cellulosethiourethanes which are reacted with the acrylic acid derivative toproduce the ethers of the invention may beprepared by any suitablemethod. They may result from the action of a primary or secondary amineon a xantho fatty acid obtained by reacting a cellulose xanthate with amonohalogenated acid, such as chloracetic acid. Preferably, however, thecellulose thiourethane is a colorless product obtained byreacting'viscose with a salt of a dior tri-valent metal, such as zincsulfate, to form a metal complex which is then reacted with the primaryor secondary amine, as described in my pending application Serial No.65,742 filed December 16, 1948, now Patent No. 2,705,231. In thepreferred embodiment, the ratio of thiourethane groups to anhydroglucoseunits is from 1:2 to 1:10. Preferably, also, the cellulose thiourethaneis soluble in dilute aqueous alkaline solution, and the reaction thereofwith the acrylic derivative is carried out in an aqueous alkalinesolution at temperatures below the polymerization temperature for theacrylic derivative.

Since the cyano-, amido-, and alkyl-substituted amido groups arehydrolyzable to the carboxyl group under alkaline conditions, theconcentration of alkali in the reacting solution must be carefullycontrolled if partial or complete hydrolysis of those groups is to beavoided. In accordance with this invention the cellulose thiourethaneand acrylic derivative are reacted in an aqueous solution of l to 4%,most desirably 2 to 3% of an alkali metal hydroxide such as sodium,lithium, or potassium hydroxide at a temperature varying inversely withthe alkali concentration between 45 and 15 C., preferably 35 and 25 C.,for a time varying with the alkali concentration and temperature between2 and 8 hours, most desirably 4 and 6 hours, using from 10 to 55,preferably from 25 to 50 moles of acrylic derivative to one mole ofcellulose thiourethane. Under these conditions, ethers in which theratio of cyanoethyl 2-amidoethyl-, or alkyl-substituted Z-amidoethylgroups to anhydroglucose units is from 0.75:1 to 1.75:1 are obtained.

The thiourethanes of the cellulose ethers may be isolated from thereaction mass by neutralizing the alkali or by pouring the reactionsolution into a precipitating liquid and occur as powdery or fibroussolids which are colorless or substantially colorless.

The new products are characterized by excellent receptivity for both theacid wool and cellulose acetate type dyestulfs and exhibit plasticproperties. They may be extruded, as such or in mixtures with otherplastic materials, to form fibers, films, tapes, tubes, ribbons, rods orother shaped articles which can be dyed very satisfactorily to deep fastshades under conventional wooldyeing conditions. Thus, the cyanoethyl-,and amidoor alkyl-substituted amidoethyl-cellulose thiourethanes may beheated, alone or in mixtures with other plastic material, to obtain ahot melt which can be extruded to form filaments, yarn, or unsupportedfilms, or to provide a suitable substrate with a coating or film. Forinstance, the ethers may be melted in a heated cylinder or the like andpumped through a spinneret or other extruding device, or they may be fedinto. a conventional screw mixer-extruder and extruded as a cylindricalrod which is broken into small pieces and fed into a screw-extruder inwhich it is melted and forced through a spinneret to form filaments orthrough an adjustable slit-like orifice in the manner customarilyemployed in the continuous manufacture of pellicles or films.

The products of the invention are soluble in dimethylformamide anddimethylacetamide, and those in which the ratio of substituted-ethylgroups to anhydroglucose units is between 1:1 and 1.75:1 are alsogenerally soluble in acetone. The thiourethane ethers may be dissolvedin the solvents therefor and spun into filaments or yarns by the knownwetor dry-spinning processes. Or the solutions may be cast into films,used as coating compositions, as adhesives, or for laminating similar ordissimilar surfaces. The new ethers may also be swollen or plasticizedby means of acetone, dimethylformamide or dimethylacetamide to obtainplastic masses or solid solutions which may be extruded or molded, bycontrolling the amount of solvent used.

The ethers may be molded by compression or injection molding techniques,with or without the addition of mold ing adjuvants including fillers,pla ti i i g ag W5 pigments, special effect materials, mold lubricants,etc, and with or without preliminary shaping to convenient pellet form.Massive molded articles of diverse size and cross-section may beobtained and dyed with an acid dye under usual wool-dyeing conditions orwith a cellulose acetate (dispel-sol) type dye.

Another important use for the new thiourethanes of cellulose ethers isas modifying or blending agents for plastic materials to impart dyereceptivity toshaped articles formed from the blends. The ethers arecompatible with such plastic fiber-forming and moldable materials ascellulose acetate and thermoplastic resins, and may be blended withthose base materials. Thus, a thiourethane of a cellulose ether withinthe scope of the invent-ion may be mixed with commercial celluloseacetate and the mixtrim may be dissolved in a solvent for the ester andether, or a thiourethane of the cellulose ether may be added to a dopecomprising the cellulose acetate and a solvent for the ester and thethiourethane of the ether, prior to spinning, casing or otherwiseshaping the dope. Dimethylformamide and dimethylacetamide, in which theether thiourethanes are soluble are also solvents for commercialcellulose acetate, and those solvents may be used in preparing spinningor casting solutions or dopes of the blends. When the solvent for thecellulose acetate is acetone, the acetone-soluble thiourethanes of thecellulose ethers are used in preparing the blends.

The thiourethanes of the cellulose ethers may also. be mixed withnatural or synthetic thermoplastic resins. and extruded or moldedby'known methods. The components of these compositions may be mixed insolution and extruded or the dry, finely divided ingredients may beintimately mixed, for example in. a Banbury mixer or on milling rolls,and dissolved in a suitable solvent. Or the dry mixture may be molded bycompression or injection l in met s- In molding the thiourethanes of thecellulose ethers, or mixtures thereof with other plastic materialsvarious molding adjuvants may be introduced into the moldingcomposition, and when blends or mixtures of the cellulose etherthiourcthanes with other plastic materials are. used, the adjuvant,which may be afiller, plasticizer, mold lubricant,

and/or special effect material, may be mixed with either Y of theprimaIy components before they are mixed. to gether or conjointly withcompounding thereof.

Fillers which may be used in conjunction with molding compositionscomprising the thiourethanes of the cellulose ethers includealpha-cellulose, wood. flour, walnut shell, flour, asbestos in the formof a powder; or long or shortv fibers, finely divided silicon carbide,carbon black, diatomaceous earth, slate dust, powdered rutile, powderedor flake mica, powdered quartz, fibers and cloth cuttings (e. g. fibersor cloth cuttings of silk, liayOn, wool, linen, cotton, nylon, glass, orpolymeric or copolymeric acrylonitrile), ground cork, sand, etc.

Useful plasticizing agents include phthalic acid esters such as thedimethyl, diethyl, dimethyl glycol, diethyl glycol, dibutyl glycol anddioctylphthalates, triethylcitrate, triacetin, benzyl benzoate and otherknown plasticizers for cellulose acetate and the synthetic thermoplasticresins.

As mold lubricants there may be used zinc steal-ate, calcium stearate,mixtures thereof, or natural or synthetic waxes.

Many thermoplastic or initially thermoplastic resins are compatible withand may be blended with the thiourethanes of cellulose ethers of thisinvention, including the polyamides such as nylon, and polyesters,particularly polymethylene terephthalates, and the syntheticthermoplastic resins obtained by the polymerization orinterpolymerization of one or more polymerizable monoethylenicallyunsaturated monomers. Examples of these resins are polystyrene,polyethylene, polymethacrylate, polyvinyl chloride, polyvinylidenechloride, copolymers of vinyl chloride and vinyl acetate, and copolymersof vinyl chloride and vinylidene chloride (e. g., the product availablecommercially under the tradename Saran).

A specific group of synthetic thermoplastic resinous materials which maybe blended with and modified by the thiourethanes of cclulose ethers arethose acrylonitrile polymers containing, by weight in the polymer mole-0 cule, at least 50% of acrylonitrile. The polymer may bepolyacrylonitrile or a copolymer of aerylonitrile with at least oneother monoethylenically unsaturated monomer which is copolymerizablewith acrylonitrile.

Monomers which may be copolymerized with acrylonitrile to produce binaryor ternary copolymers for blending with the thiourethanes of thecellulose ethers include: acrylic, alpha-chloracrylic and methacrylicacids; methyl met-hacrylate, ethyl methacrylate, butyl methacrylate,octyl methacrylate, 2-nitro-2-methy-lpropyl methacrylate, methoxy-methacrylate, beta-chloroethyl methacrylate and the correspondingesters of acrylic and alpha-chloracrylic acids; vinyl chloride, vinylfluoride, vinyl bromide; vinylidene chloride, l-chloro-l-bromo-ethylene,vinylidene bromide, l-fluoro-1-chlorethylenc, 1,1-difluoroethylene; methacrylonitrile, alpha-chloracrylonitrile; acrylamide, methacrylamide,N,N-dimethylacrylamide, alpha-chloracryL amide or monoalkyl substitutionproducts thereof; methyl vinyl ketone and methyl isopropyl ketone; vinylcarboxylates such as vinyl acetate, vinyl chloracetate, vinyl propionateand v-inylstearate; N-vinylimides such as N-vinyl phthalimide andN-vinyl succinimide; methylenc-malonic esters; itaconic acid anditaconic esters; trifiuorethylene; N-vinyl carbazole andvinyl-substituted hetcrocyclic amines such as the vinylpyridinesincluding those having hydrocarbon groups containing a total of not morethan four carbon atoms attached to the pyridine nucleus, 0. g.,2-vinyl-pyridine, 2-methyl-5-vinylpridine, vinyl imidazolcs, e. g.,l-vinylimidazolc and N-vinylimidazolo, l-vinyl-2- methylimidazole, etc.;vinyl furane; butyl vinyl sultonc, ethyl vinyl sulfone; ethylene,propylene, isobutylene, butene-l and butene-2; alkyl vinyl ethers; vinylsulfonic acid; ethylene-alpha, beta-dicarboxylic acid or theiranhydrides or derivatives such as diethyl fumaratc, diethyl maleatc,diethyl citraconate, diethyl mcsaconate; styrene, vinylnaphthaleneandthe like.

While the proportion of polymerized acrylonitrilc in the baseacrylonit-rile polymer is at least 50%, it is frequently much higherdepending on the ultimateuseof the blend of polymer and thiourethane ofcellulose ether. If the polymer is an acrylonitrile copolymer and theblend with the cellulose ether; thiourethane is. to be spun from asolution of the blend to forrnfilamcntsor threads, the copolymer shouldcontain at least 80% by weight of acrylonitrile in the molecule and not,in, excess of 20% by weight of the other monomer or monomers. Binarycopolymers containing by weight in the polymeu molecule from 80% to 99%acrylonitrile and 1% to 20% of another monomer, and ternary copolymerscontaining, by weight in the polymer molecule, 80% to 98% acryloni- 0trile and l to 19% each of two of the other monomers dimethylacet'amide.Since these solvents also dissolve the thiourethanes of cellulose ethersof the invention, they may be used in preparing spinning and castingsolutions of the mixtures of acrylonitrile polymers and thethiourethanes.

The acrylonitrile polymers containing less than 80% by weight ofacrylonitrile in the polymer molecule are not only soluble indimethylformamide and dimethylacetamide but are also soluble in morecommon organic solvents, such as acetone, which do not dissolve thepolymers of higher acrylonitrile content. Those thiourethanes ofcellulose ethers which are soluble in acetone may be blended with theacetone-soluble acrylonitrile polymers and dissolved in acetone toobtain solutions which are cast into films, applied as coatings, and soforth.

The molecular weight of the thermoplastic resin mixed with the celluloseether thiourethane may vary rather widely, depending on the use forwhich the blend or mixture is intended. Preferably, the resin has amolecular weight of at least 5,000, but when the composition comprises ablend of a cellulose ether thiourethane and a polymeric materialcontaining at least 80% of polymerized acrylonitrile which is to beformed into filaments or yarns, higher molecular weights are requiredand the polymer may have a molecular weight up to 250,000 or evenhigher.

Although the cellulose ether thiourethanes of the invention can beblended with base materials which are more or less receptive to dyes,they are most valuable as blending or modifying agents for polymericmaterials which are not dyed satisfactorily in baths containing theacetate dyes or wool type acid dyes, or which are not dyedsatisfactorily by those dyes unless the bath contains special assistantsthe use of which complicates the dyeing operation and increases itscost.

The organic acid esters of cellulose, which are polymeric esters andexemplified by cellulose acetate, are hydrophobic materials not readilypenetrated by wateror aqueous media. The common method of dyeingarticles formed from those esters with both acetate dyes and wool typeacid dyes involves the use of baths containing an agent which swells orpartially dissolves the cellulose ester to facilitate entry of thedyebath into the yarn or other article. Articles formed from blends ofthe cellulose organic acid esters with the thiourethanes of celluloseethers of the invention can be dyed in aqueous baths containing theacetate dyes or acid wool type dyes in the absence of special swellingagents or partial solvents for the cellulose ester. Likewise,acrylonitrile polymers which do not accept the acid dyestuffs and arenot colored to deep shades in baths containing the acetate dyes can bedyed under normal conditions in aqueous solutions or suspensions ofthose dyes if they are blended with the cellulose ether thiourethanes.In all cases, articles formed from blends of an acrylonitrile polymerand cellulose ether thiourethane were dyed to deeper, faster shades inaqueous baths containing a wool type acid dye or an acetate dye thancontrol articles formed from the acrylonitrile polymer alone.

The dye receptivity of cellulose acetate and the thermoplastic resinscan be modified by the use of the cellulose ether thiourethanes inamounts which do not result in any depreciation in the good tensilestrength or other characteristic physical properties of filaments, yarnsor other extruded or molded articles as compared to those properties ofarticles consisting of the cellulose esters or thermoplastic resins. Ingeneral, the cellulose ether thiourethane may be present in the blend inan amount of 2% to on the weight of the blend.

The ethers and mixtures thereof with other at least initiallythermoplastic materials exhibit good plastic flow during molding, andarticles molded therefrom are clear, substantially colorless, and have agood surface appearance.

The following examples, in which the parts given are by weight unlessotherwise specified, illustrate specific embodiments of the invention.The Rockwell hardness of the molded articles given was determined bymeans of the well-known Rockwell hardness tester.

Example I An aqueous alkaline solution of cellulose phenylthiourethane(prepared by the method described in my pending application Serial No.65,742 now Patent No. 2,705,231) and containing 1 phenylthiourethanegroup per 3 anhydroglucose units was obtained by suspending 74 parts ofthe thiourethane in 3000 parts of water, mixing, and adding a mixture of111 parts of sodium hydroxide dissolved in 515 parts of water. Themixture was chilled to room temperature and 378 parts of acrylonitrilewereadded. The mixture was stirred for six hours at 25 C. As thereaction proceeded, the product precipitated and on completion of thereaction the mixture was neutralized with acetic acid and filtered. Theresidue on the filter was washed four times with water at roomtemperature, with continuous agitation during the washings andfiltration between each washing. The product was finally washed withwater at 50 C. for four hours. The purified ether contained 8.7%nitrogen, equivalent to 1.5 cyanoethyl groups per anhydroglucose unit.It was soluble in acetone, dimethylformamide and dimethylacetamide.

Example 2 Weighed portions of the phenylthiourethane of cyanoethylcellulose of Example 1 were placed in cylindrical compression moldshaving a diameter of 1.25 inch. The molds were placed in a hydraulicpress and heated by band heaters to 210 C. and then subjected to 4000lbs/sq. inch pressure for 5 minutes at that temperature. The molds werecooled and opened; the molded rods were removed. These rods weretranslucent, and had a Rockwell hardness of M-95.

Example 3 A 2% solution of an ethylthiourethane of cellulose having adegree of substitution of one ethylthiourethane group per 6.5anhydroglucose units in 2% sodium hydroxide was made by suspending 87parts of the thiourethane in 3,700 parts of water, mixing, and thenadding a solution of 130.5 parts of sodium hydroxide in 432.5 parts ofwater. To this solution there were added, with stirring, 1166 parts ofacrylonitrile and the reaction mixture was stirred at 25 C. for sixhours, after which the mixture was neutralized with acetic acid andfiltered. The residue on the filter was washed four times with water at25 C. with continuous agitation and with filtration between washings. Itwas finally washed with isopropanol at 50 C., filtered and dried at 50C., for about three hours. The purified ether occurred as a white powdercontaining 9.40% combined nitrogen, corresponding to 1.62 cyanoethylgroups per anhydroglucose unit. The ether was analyzed for carboxylcontent and found to contain 0.024% COOH, indicating very slighthydrolysis of the CN group. It was soluble in dimethylformamide anddimethylacetamide, insoluble in acetone and acetone-water mixtures.

Example 4 The ethylthiourethane of cyanoethyl cellulose of EX- ample 3was molded as in Example 1 at 215 C. Translucent rods having a Rockwellhardness of M-89 were obtained.

A standardized dyebath was prepared by dissolving 5% of Glaubers salt,3% of sulfuric acid (96%) and 2% of the acid dye Wool Fast Scarlet G.Supra (C. I. #252) percentages on the weight of the article to be dyedin water. The articles to be dyed were entered into the bath at 55 C.,the bath was brought to the boil in 10 minutes, and boiled for 20minutes.

The rods of this example were dyed to a good red shade in the dyebathdescribed.

Example About 87 parts of cellulose dimethylthiourethane (prepared bythe method of my pending application Serial No. 65,742 now Patent No.2,705,231, and containing one dimethylthiourethane group per 2.6anhydroglucose units) were suspended in 3,700 parts of water, thesuspension was mixed, and 130.5 parts of sodium hydroxide in 432.5 partsof water were added. A 2% solution of the thiourethane in 2% sodiumhydroxide was obtained. To this there were added, with stirring, 1166parts of acrylonitrile. The reaction mixture was stirred at 25 C. forsix hours, after which it was neutralized with 95% acetic acid andfiltered. The residue on the filter was washed four times with water atroom temperature, with continuous agitation during the Washing andfiltration between washings. It was finally washed with isopropanol at50 C., filtered and dried at 50 C. The purified ether occurred as awhite powder containing 7.39% combined nitrogen, corresponding to 1.1cyanoethyl group per anhydroglucose unit.

Example 6 A solution of 2% of the phenylthiourethane of Example 1 in 1%aqueous sodium hydroxide was prepared by the method of Example 1. To98.5 parts of this solution there were added 35 parts of acrylamide, andthe mixture was stirred at 25 C. for six hours, after which it waspoured into an aqueous solution of acetic acid and soduim acetate toprecipitate the crude phenylthiourethane of amidoethyl cellulose. Theprecipitate was filtered and washed repeatedly with water until it wasacid-free. it was then washed with isopropanol at 50 C. and dried. Itcontained 3.10% combined nitrogen, corresponding to 0.09 2-amidoethylgroups per anhydroglucose unit.

Example 7 A solution of 2% of the cellulose phenylthiourethane ofExample 1 in 1% aqueous sodium hydroxide was obtained by the method ofExample 1. To 98.5 parts of this solution there were added 50 parts ofN,N-dimethylacrylamide. The reaction mixture was stirred at C. for sixhours, and then poured into an aqueous solution of 10% acetic acid and20% of sodium acetate to precipitate the crude dimethylamidoethylcellulose phenylthiourethane. The precipitate was filtered, washed withwater until acid-free, finally washed with isopropanol at C., and dried.It contained 2.81% combined nitrogen, equal to a degree of substitutionof 0.06 Z-dimethylamidoethyl groups per anhydroglucose unit.

Example 8 Viscose was prepared by impregnating 200 parts of cellulose insheet form with 17.8% sodium hydroxide solution at 18 C, for two hours,pressing to three times the weight of the cellulose, shredding andmercerizing the cellulose for 72 hours at 18 C., xanthating the alkalicellulose with 85% carbon disulfide (on the weight of the cellulose) atbetween 18 and 25 C. for five hours, and then dissolving the xanthate in3000 parts of water. The viscose thus obtained was aged for 24 hours at10 C.. and diluted with 8000 parts of water. 800 parts of a 5% (byvolume) solution of acetic acid were added and the mass was stirred forone hour. A mixture of 200 parts chloraceti'c acid and 178 parts ofsodium bicarbonate dissolved in- 800 parts of water was slowly added andmixed for 24 hours at 25 C. At the end of this time, a solution of 400parts of Z-aminopyridine in 200 parts of water was added. The mass wasagitated at 25 C. for about 144 hours to precipitate the crude cellulosepyridylthiourethane. The precipitate was filtered, washed several timeswith water, once with isopropanol at 50 C., and again with water. Thepurified product was dried at 50 C. and 4 mm. pressure. It contained3.65% combined nitrogen, corresponding to one pyridylthiourethane groupper four anhydroglucoseunits.

290 parts of the pyridylthiourethane were dissolved in 8,688 parts ofwater containing 362 parts of sodium hydroxide. To this solution at 25C. there were added 1350 parts of acrylonitrile. The mixture was stirredfor 1 six hours, after which it was neutralized with acetic acid andfiltered. The residue was washed several times with isopropanol withagitation during the washing and filtration between each washing. Thepurified product was dried. It contained 9.53% combined nitrogen,corresponding to a pyridylthiourethane of cyanoethyl cellulosecontaining 1.56 cyanoethyl groups per anhydroglucose unit.

Example 9 A solution of 2% of a cellulose phenylthiourethane containingone phenylthiourethane group per three anhydroglucose units in 1%aqueous sodium hydroxide was prepared by the method of Example 1. Aboutparts of acrylonitrile were added to 985 parts of the alkaline solutionand the mixture was stirred at 25 C. After 15 minutes, two hours, andsix hours, portions of the mixture were poured into an aqueous solutionof 10% acetic acid and 15% sodium acetate. The precipitates obtainedwere washed repeatedly with water, finally with isopropanol at 50 C. Theproduct obtained after the 15- minute reaction period was insoluble indimethylacetamide, while the products obtained after the two-hour andsix-hour reaction periods were soluble therein. The phenylthiourethaneof cyanoethyl cellulose obtained after a reaction time of two hourscontained 6.96% combined nitrogen, corresponding to a ratio ofcyanoethyl groups to anhydroglucose units of 0.93:1.

Example 10 A solution of 2% of the cellulose phenylthiourethane ofExample 1 in aqueous 1% sodium hydroxide was prepared by the method ofExample 1, and heated at 35 C. with 280 parts of acrylonitrile for sixhours. The reaction product was isolated and purified as in Example 9.It contained 8.70% combined nitrogen, corresponding to 1.45 cyanoethylgroups per anhydroglucose unit. It was soluble in dimethylformamide,dimethylacetamide and acetone.

Example 11 Example 10 was repeated, except that the reaction temperaturewas 45 C. The ether thus produced contained 7.09% combined nitrogenwhich corresponds to a degree of substitution of 0.96 cyanoethyl groupper anhydroglucose unit.

Example 12 Example 10 was repeated, using 56 parts of acrylonitrile. Theresulting purified ether contained 6.31% nitrogen, corresponding to 0.75cyanoethyl group per anhydroglucose unit.

Example 13 Example 10 was repeated, using 140 parts of acrylonitri-le.The purified phenylthiourethane of the cyanoethyl ether contained 6.63%nitrogen, which corresponds to 0.85 cyanoethyl group per anhydroglueoseunit.

Example 14 A solution of 2% of the phenylthiourethane of cellulose inaqueous 3% sodium hydroxide was prepared by the method of Example 1. To985 parts of the solution there were added 146 parts of acrylonitrile.The mix ture was stirred for six hours at 25 C. The cyanoethyl ether wasprecipitated and purified as in Example 9. By analysis it was found tocontain 7.57% combined 7 nitrogen, corresponding to a cyanoethyl groupto anhydroglucose unit ratio of 1:1.

Example 15 A solution of 2% of the cellulose phenylthiourethane in 4%.aqueous sodium hydroxide was made by the method of Example 1. 146 partsof acrylonitrile were added to 985 parts of the solution and the mixturewas stirred for six hours at 25 C. The cyanoethyl ether was precipitatedand purified as in Example 9. On analysis it was found to contain 6.91%combined nitrogen which corresponds to a D. S. (degree of substitution)of 0.92 cyanoethyl group per anhydroglucose unit.

Example 16 About 14 parts of a blend of 88 parts of a copolymer of 97%acrylonitrile and 3% vinyl acetate (sp. vise. 0.26), with 12 parts ofthe ethylthiourethane of cyanoethyl cellulose of Example 3 was dissolvedin 86 parts of dimethylacetamide. The 14% solution was pumped at a speedof 12 ml./min. through a spinneret having 40 holes into a bathcomprising 60% of dimethylacetamide and 40% of water at 50 C. The yarnsthus formed were withdrawn from the bath after an immersion of 18inches, withdrawn over a godet at a speed of 25 ft./rnin. and washedwith water at 95 C. as they passed from the oath to the godet. The yarnswere given a godet stretch of 150%, washed with water at 95 C. until theresidual dimethylacetamide content was less than 2%, dried onsteam-heated rolls at 100 C., and stretched 350% in an atmosphere ofsteam under a pressure of 60 lbs/sq. in.

The yarns could be dyed by cellulose acetate dyestufis. In an aqueousbath containing 6% Celliton Fast Violet Ba (Pr. #240) (ratio of bath toyarns 40:1) in which the yarns were held for one hour at 200 F., theydyed to a deeper shade than control yarns of the 97% acrylonitrile-3vinyl acetate copolymer produced and aftertreated in the same manner. Ina bath containing 6% Celliton Fast Black BTNA and under the same dyeingconditions, the yarns of the blend were dyed to a deeper shade than thecontrol yarns.

Example 17 A 16% dimethylacetamide solution of a blend of 88 parts of acopolymer of 97% acrylonitrile and 3% vinyl acetate with 12 parts of thedimethylthiourethane of cyanoethyl cellulose of Example 5 was prepared.The solution was spun into yarns as in Example 16, except that the yarnswere withdrawn from the bath at a speed of 32 ft./rnin. and stretched100% simultaneously with washing thereof as they proceeded from thebath.

Different aqueous dyebaths were prepared containing of sulfuric acidand, respectively, the acid dyestuffs as follows: 2% Crocein ScarletM00, 2% Acid Dark Green, A (C. I. No. 247), and 6% W001 Navy Blue 213.Difierent batches of the yarns comprising the blend of acrylonitrilepolymer and the dimethylthiourethane of cyanoethylcellulose were enteredinto the baths at 200 F. and held therein for one hour. Ratio of bath toyarns 40:1.

Difierent aqueous dyebaths were prepared containing, respectively, thefollowing cellulose acetate dyestufis: 2% Eastone Orange 3R, 4% EastmanBlue, BNN, 4% Celliton Fast Violet BA (Pr. #240), and 6% Celliton FastBlue BRA (Br. #233). Difierent batches of the yarns comprising the blendas described above were dyed in these baths at 200 F. for one hour.Ratio of bath to yarns 40: 1.

Example 18 A 14% dimethylacetamide solution of a blend of 92 parts of acopolymer of 97% acrylonitrile and 3% vinyl acetate (specific viscosity0.22 measured as 0.1 gm. in 100 ml. of dimethylformamide) and 8 parts ofthe pyridylthiourethane of cyanoethyl cellulose of Example 8 wasprepared. The solution was cast to a film which was dyed with Wool FastScarlet G Supra in a bath prepared as described in Example 4. The dyeacceptance of the blend film was considerably better than that of acontrol film of the acrylonitrile-vinyl acetate copolymer.

Example 19 A 14% dimethylacetamide solution of a blend of 92 parts ofpolyacrylonitrile and 8 parts of the pyridylthiourethane of cyanoethylcellulose of Example 8 was prepared. it was cast to films which weredyed to a deeper shade of red in a bath as in Example 18 than a controlfilm of the copolymer.

Various modifications may be made in practicing the invention. Forinstance in Example 6, instead of acrylamide there may be used anacrylamide salt, such as the sulfate.

Other modifications and changes may also be made without departing fromthe spirit and scope of the invention as defined in the appended claims.

I claim:

1. As a new compound, a thiourethane of an ether of cellulose, saidcompound having the formula 5 I Cell-O-(l-N omoInX R in which cell isthe cellulose molecule, X is selected from the class consisting of CNgroups and CONYY groups in which Y and Y are each selected from thegroup consisting of hydrogen and alkyl radicals containing from 1 to 3carbon atoms, and R and R are each selected from the group consisting ofhydrogen, saturated and unsaturated aliphatic hydrocarbon radicalscontaining from 1 to 8 carbon atoms, alicyclic radicals having a single4- to 6-membered carbocyclic ring, heterocyclic nitrogen radicals havinga single 5- to 6-membered ring, aryl radicals of the benzene seriescontaining no hydrocarbon group attached to the benzene ring, and arylradicals of the benzene series having hydrocarbon groups containing atotal of not more than two carbon atoms attached to the benzene ring.

2. The phenylthiourethane of 2-cyanoethyl cellulose.

3. The ethylthiourethane of Z-cyanoethyl cellulose.

4. The dimethylthiourethane of Z-cyanoethyl cellulose.

5. The pyridylthiourethane of Z-cyanoetheyl cellulose.

6. The benzylthiourethane of 2-cyanoethyl cellulose.

7. A process of producing a cyanoethylated cellulose thiourethane whichcomprises reacting a thiourethane of cellulose with acrylonitrile in aratio of from 1 mole of the thiourethane to 10 to 55 moles ofacrylonitrile in an aqueous solution of from 1 to 4% of alkali metalhydroxide and at a temperature of 15 to 45 C. for between 2 to 8 hours.

8. Process of claim 7 in which the thiourethane group is selected fromthe group consisting of thiourethane, phenylthiourethane,phenylethylthiourethane, isopropylthiourethane, amylthiourethane,benzylthiourethane, cyclohexylthiourethane, octylthiourethane,dibenzylthiourethane, dibutylthiourethane, diethylthiourethane,methallylthiourethane, pyrrolylthiourethane, and cyclobutylthiourethane.

References Cited in the file of this patent UNITED STATES PATENTS OTHERREFERENCES Fieser et al.: Organic Chemistry, 2d ed., Heath, page 32.

Whitmore: Organic Chemistry, 2d ed., pages 727-8 and 741-2.

1. AS A NEW COMPOUND, A THIOURETHANE OF AN ETHER OF CELLULOSE, SAIDCOMPOUND HAVING THE FORMULA